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Progress Report Series No. 42 December 1949
AGRICULTURAL EXPERIMENT STATION
of The Alabama Polytechnic Institute, 
Auburn, Ala.
S* * * M.J. Funchess, 
Director
CONTROL of the IMPORTED FIRE ANT
F. S. ARANT, Entomologist
i. 6. EDEN, Assistant Entomologist
For more than 20 years, the Gulf Coast
area of Alabama has been troubled by the
imported, or mound-building, fire ant. In
recent years this ant has spread to other
areas and now occurs in at least 10 coun-
ties, principally in southwestern Alabama,
but extending as far north as Perry County.
The imported fire ant is an economical-
ly important pest because it freauently at-
tacks germinating seed and young tender
plants, and it builds unsightly mounds
which may damage machinery such as mowers
and combines. Its painful sting makes it an
annoying pest. The ant is a general feeder,
-a d-it is -fre-entlya-- househd as well as
a field pest.
The imported fire ant lives in nests or
colonies,. which may be numerous along road-
ways and ditch banks, in permanent pas-
tures, and in other uncultivated areas.
Mounds vary in height from approximately
6 inches to nearly 2 feet. The nest ex-
tends through the mound and into the ground
beneath. Euring the spring and early sumner
winged males and females are ouite numerous
in the nests. jThese winged ants swarm out
of the mounds, fly for varying distances,
and establish new colonies.
Experiments have been conducted on the
control of the imported fire ant during
1949 at the Gulf Coast Substation, Fair-
hope, and at the State Prison Farm, Atmore.
These experiments involved seven separate
tests, covering approximately 40 acres of
land. Tentative recommendations for the
control of this pest, based on the results
of these experiments, are reported here.
MOUND TREATMENTS
Fire ant nests are freauently located in
such places that the only practical treat-
ment consists of applying insecticides 
to
the mound itself. Chlordane either 
as a 10
per cent dust or as a 2 per cent emulsion
spray was effective for mound treatments.
The dust was applied 
at the rate of at
least 2 ounces per hill. The spray was
applied at the rate of at least one-half
pint per hill. The mounds were broken down
and the insecticide was mixed with the 
soil
in the mounds. An ordinary garden rake was
satisfactory for this purpose. Poth of
these methods gave practically 100 per cent
elimination of colonies in experiments
conducted at Atmore.
.An alternate method of treating 
hills
consisted of driving three evenly-spaced
holes approximately 18 inches 
deep into the
nest. One-third of the chlordane 
dust or
spray was then placed into each 
hole and
covered over with soil. Fesults from 
this
method were satisfactory 
but slightly less
effective than where the insecticide was
mixed with soil in the mound.
Other insecticides that gave good 
re-
sults consisted of 20 per cent toxaphene
dust, 2% per cent dust of a new product
named '118', 3 per cent gamma BHC- 5 per
cent 1- 'T (cotton dust), and a 1 per cent
dust of compound '497.' Additional experi-
ments are being conducted on the effective-
ness of these materials. Where chlordane is
available, it is recommended at present as
the first choice for use against this pest.
AREA TREATMENTS
Experiments were conducted for control
of ants on an area basis by broadcast
treatments. Twenty to 40 pounds of 10 per
cent chlordane dust or 10 to 20 gallons
of 2Y2 per cent emulsion spray was applied
per acre. Treatments included application
of chlordane before disking, after 
disking,
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and without disking. The results indicat-
ed that above 90 per cent control of all
active mounds was obtained when 20 pounds
of 10 per cent dust was applied either be-
fore or after thorough disking of the soil.
This dosage is recommended for economical
control.
In one experiment 40 pounds of 10 per
cent chlordane dust per acre applied broad-
cast and disked-in gave 100 per cent elim-
ination of all ants in the area over a 90-
day period. This treatment was in a field
free of roots and stumps and the entire
surface of the soil was disked. In other
areas where roots and stumps interfered
with the disking, the treatment was some-
what less effective but still highly satis-
factory. Several days were required to kill
most of the ants. However, the insecticide
continued to kill for weeks after the
treatment.
Application of chlordane dust without
disking was much less effective than when
the soil was disked and when the mounds
were torn down. However, chlordane sprays
applied at the rate of 2 to 4 pounds of
technical chlordane per acre showed promise
of control without disking.
TIME TO APPLY TREATMENTS
Exact information on the best time of
year to apply treatments is not available.
From February to May should be the best
time to treat either hills or areas, since
the winged forms swarm from the nests dur-
ing the spring and early summer to estab-
lish new colonies.
The assistance and cooperation of Otto
Brown and Harold Yates, superintendent and
assistant superintendent of the Gulf Coast
Substation, and of T.P. Whitten, assistaht
horticulturist,Atmore, are acknowledged by
the authors.